Ch 1 Flashcards
1
Q
Microbiology revolves around two themes:
A
- understanding basic life processes
- applying that knowledge to the benefits of humans
2
Q
___ are excellent models for understanding cellular processes in unicellular and multicellular organisms.
A
Microbes
3
Q
Microbes play important roles in ___, ___, and ___.
A
Medicine, agriculture, and industry
4
Q
The importance of microorganisms:
A
- oldest form of life
- largest mass of living material on earth
- carry out major processes for biogeochemical cycles
- can live in places unsuitable for other organisms
- other life forms require microbes to survive
5
Q
The cell is..
A
A dynamic entity that forms the fundamental unit of life
6
Q
Cytoplasmic (cell) membrane:
A
Barrier that separates the inside of the cell from the outside environment
7
Q
Cytoplasm:
A
Aqueous mixture of macromolecules, ions, and ribosome
8
Q
Ribosomes:
A
Protein-synthesizing structures
9
Q
Cell wall:
A
Present in most microbes; confers structural strength
10
Q
All cells have the following in common:
A
- cytoplasmic membrane
- cytoplasm
- ribosomes
- cell wall
11
Q
Prokaryotes
A
- no membrane-enclosed organelles, no nucleus
- generally smaller than eukaryotic cells
12
Q
Eukaryotes
A
- DNA enclosed in a membrane-bound nucleus
- cells are generally larger and more complex
- contain organelles
13
Q
Genome:
A
A cells full complement of genes
14
Q
Eukaryotic DNA is ___ and found within the ___.
A
Linear, nucleus
15
Q
Eukaryotic cells usually have more than one ___.
A
Chromosome
16
Q
Eukaryotic cells typically have ___ copies of each chromosome.
A
Two
17
Q
During cell division, nucleus divides by ____.
A
Mitosis
18
Q
During sexual reproduction, the genome is halved by ___.
A
Meiosis
19
Q
Prokaryotic cells generally have a single, circular DNA molecule called a ___.
A
Chromosome
20
Q
DNA aggregates to form the ___.
A
Nucleoid region
21
Q
Prokaryotes also may have small amounts of extrachromosomal DNA called ___ that confer special properties.
A
Plasmids
22
Q
E. coli genome vs. human cell
A
E. coli
4.64 million base pairs
4,300 genes
Human cell
1,000x more DNA per cell than E. coli
7x more genes than E. coli
23
Q
Metabolism:
A
Chemical transformation of nutrients
24
Q
Reproduction:
A
Generation of two cells from one
25
Differentiation:
Synthesis of new substances or structures that modify the cell
26
Communication:
Generation of, and response to, chemical signals
27
Movement:
Via self-propulsion, many forms in microbes
28
Evolution:
Genetic changes in cells that are transferred to offspring
The process of change over time that results in new varieties and species of organisms
29
Enzymes:
Protein catalysts of the cell that accelerate chemical reactions
30
Cells store and process information that is eventually passed on to offspring during reproduction through ___ and ___.
DNA and evolution
31
DNA stands for:
Deoxyribonucleic acid
32
Transcription:
DNA produces RNA
33
DNA produces RNA
Transcription
34
Translation:
RNA makes protein
35
RNA makes protein
Translation
36
Growth:
The link between cells as machines and cells as coding devices
37
Last universal common ancestor (LUCA):
Common ancestral cell from which all cells descended
38
Earth is ___ years old
4.6 billion
39
First cells appeared between ___ and ___ years ago
3.8-3.9 billion
40
The atmosphere was anoxic until about ___ years ago.
2 billion
41
Metabolisms were exclusively ___ until evolution of oxygen-producing phototrophs
Anaerobic
42
Life was exclusively microbial until about ___ years ago.
One billion
43
Phylogeny:
- Evolutionary relationships between organisms
44
Ribosomal RNA (rRNA) is excellent for determining ___.
Phylogeny
45
Relationships visualized on a ___ ___.
Phylogenetic tree
46
Relationships can be deduced by comparing ___ ___ in the different specimens
Genetic information
47
Comparative rRNA sequencing has defined three distinct lineages of cells called ___.
Domains
48
Three domains:
Bacteria (prokaryotic)
Archaea (prokaryotic)
Eukarya (eukaryotic)
49
Archaea are more closely related to ___ than ___.
Eukarya than bacteria
50
___ ___ were the ancestors of multicellular organisms.
Eukaryotic microorganisms
51
From the LUCA, evolution proceeded to form two domains:
Bacteria
| Archaea
52
Archaea later diverged to form two domains:
Archaea
| Eukarya
53
Microorganisms exist in nature in populations of interacting assemblages called ___ ___.
Microbial communities
54
The environment in which a microbial population lives is its ___.
Habitat
55
___ refers to all living organisms plus physical and chemical constituents of their environment.
Ecosystem
56
___ ___ is the study of microbes in their natural environment.
Microbial ecology
57
Diversity and abundances of microbes are controlled by ___ and ___ ___.
Resources (nutrients) and environmental conditions (temp, pH, O2)
58
The activities of microbial communities can affect the chemical and physical properties of their ___.
Habitats
59
Microbes also interact with their ___ and ___ environment.
Physical and chemical
60
Ecosystems are greatly influenced by ___ ___.
Microbial activities
61
Extremophiles:
Bacteria and archaea that can grow in extremely harsh environments
- very hot or very cold
- very acidic or very caustic
- very salty or very osmotically stressing
- very high pressure
62
Global estimate is ___ cells
5x10^30
63
Most microbial cells are found in ___ and ___ subsurfaces.
Oceanic and terrestrial
64
Microbial ___ is significant, and cells are key reservoirs of essential nutrients.
Biomass
65
Microorganisms can be both ___ and ___ to humans.
Beneficial and harmful
66
Many more microorganisms are ___ than are ___.
Beneficial, harmful
67
Many aspects of agriculture depend on ___ ___.
Microbial activities
68
Positive impacts of microorganisms and agriculture
- nitrogen-fixing bacteria
- cellulose-degrading microbes in the rumen
- regeneration of nutrients in soil and water
69
Negative impacts of microorganisms and agriculture
Diseases in plants and animals
70
High numbers of microorganisms occur in ___ and ___ ___.
Colon and oral cavity
71
Positive impacts of microorganisms and the human GI tract
- synthesize vitamins and other nutrients
| - compete with pathogens for space and resources
72
Positive impacts of microorganisms and food
- microbial transformations yield
73
Negative impacts of microorganisms and food
Microorganisms can cause food spoilage
74
The role of microbes in production of biofuels
Methane, ethanol, hydrogen
75
Bioremediation:
The role of microbes in cleaning up pollutants
76
Biotechnology:
Genetic engineering of microbes to generate products of value to humans, such as insulin
77
Microorganisms and their genetic resources
Exploitation of microbes for production of antibiotics, enzymes, and various chemicals
78
Microbiology began with the ___.
Microscope
79
Who was the first to describe microbes?
Robert Hooke
80
What did Robert Hooke do?
Illustrated the fruiting structures of molds
81
Who was the first to describe bacteria?
Antoni van Leeuwenhoek
82
Who discovered that living organisms discriminate between optical isomers?
Louis Pasteur
83
Who discovered that alcoholic fermentation was a biologically mediated process?
Louis Pasteur
84
Who disproved theory of spontaneous generation?
Louis Pasteur
85
Who developed vaccines for anthrax, fowl cholera, and rabies?
Louis Pasteur
86
When Pasteur disproved the theory of spontaneous generation it led to..
The development of methods for controlling the growth of microorganisms
87
Pasteur developed vaccines for ___, ___ ___, and ___.
Anthrax, fowl cholera, and rabies
88
Who demonstrated the link between microbes and infectious diseases?
Robert Koch
89
Koch developed techniques for..
Obtaining pure cultures of microbes
90
Koch identified causative agents of ___ and ___.
Anthrax and tuberculosis
91
Koch discovered that using solid media provided a simple way to optain ___ ___.
Pure cultures
92
Colonies:
Masses of cells
93
Koch observed that colonies have different ___, ___, and ___.
Shapes, colors, and sizes.
94
Microbial diversity:
Field that focuses on nonmedical aspects of microbiology
95
Who developed enrichment culture technique?
Martinus Beijerinck
96
Enrichment culture technique
Microbes can be isolated from natural samples in a highly selective fashion by manipulating nutrient and incubation conditions
97
Who proposed concept of chemolithotrophy?
Sergei Winogradsky
98
Chemolithotrophy
Oxidation of inorganic compounds linked to energy conservation
99
Winogradsky demonstrated that specific bacteria are linked to specific ___ ___.
Biogeochemical transformations
100
Major subdisciplines of applied microbiology:
- medical microbiology
- immunology
- agriculture microbiology
- industrial microbiology
- aquatic microbiology
- biotechnology
101
Medical microbiology:
Infectious diseases
102
Immunology:
Immune system
103
Agricultural microbiology:
Microbes associated with soil
104
Industrial microbiology:
Production of antibiotics, alcohols, and other chemicals
105
Aquatic microbiology:
Water, wastewater, and drinking water
106
Biotechnology:
Products of genetically engineered microorganisms
107
Basic science subdisciplines in microbiology
- microbial systematics
- microbial physiology
- microbial ecology
- microbial biochemistry
- bacterial genetics
- virology
108
Microbial systematics:
The science of grouping and classifying organisms
109
Microbial physiology:
Study of the nutrients that microbes require for metabolism and growth and the products that microorganisms generate
110
Microbial ecology:
Study of microbial diversity and activity in natural habitats
111
Microbial biochemistry:
Study of microbial enzymes and chemical reactions
112
Bacterial genetics:
Study of heredity and variation in bacteria
113
Virology:
Study of viruses
114
Binary fission
Asexual reproduction
115
Positive chemotaxis
Place sugar - moves towards
116
Negative chemotaxis
Place acid - moves away
117
"Hypo"
High heat
118
Saccharophiles
Sugar loving
119
Pathogenic
Able to cause disease
120
Rhizobium
Helps to fix nitrogen for plants, creates root nodules
121
Transient bacteria
The ones we pick up from our environment
122
Zone of inhabition
Big colony not allowing other bacteria to grow
123
All purpose media
You can grow anything on this media
| TSA and TSB
